Small Role Big Impact / Anime & Manga

Instances of Small Role, Big Impact in Anime and Manga.

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• The 100 Girlfriends Who Really, Really, Really, Really, Really Love You: The God of Love shows up in the first chapter, is limited to making cameos in the volume extras from that point on and doesn't reappear until Chapter 85. Yet it's only because he got distracted by Castle in the Sky while filling out Rentarou's soulmate count that Rentarou has one hundred girlfriends.
• Assassination Classroom: Aguri Yukimura only shows up in a couple of flashbacks, but she's the cause for a lot of the plot. She was both Class 3E's teacher and in an Arranged Marriage with Yanagisawa, which led to her meeting Koro-sensei before his transformation and helping make him the Cool Teacher 3E would come to love. Her death also lead to her sister Akari infiltrating 3E as Kaede Kayano in a misguided attempt to take revenge for her sister's death. And she was also the cause of Koro-sensei having a big boob fetish.
• Attack on Titan:
  • Eren Kruger only appears in Grisha Kruger's flashbacks, but is essentially responsible for all the events in the series turning out the way they did — Grisha met Kruger when he was a child and was present on the day Grisha's sister was killed. He's the reason why Grisha joined La Résistance and met his first wife Dina and it's because of him that Zeke Jaeger, the Beast Titan, was born. Zeke then betrayed his parents and they ended up on Paradis Island with the other members of their group. Kruger was then the one who saved Grisha's life and gave him the powers of the Attack Titan, which Grisha then bequeathed to his son. To top it all off, he's also the inspiration behind the protagonist's name. Safe to say that the story would be very different if he and Grisha had never met.
  • Tom Ksaver only appears in Zeke's childhood flashback, but was the one who convinced him to rat out his parents for conspiring against Marley and euthanize the Eldians. Zeke's glasses are a memento left from devouring Tom to gain the Beast Titan.
• Beastars: Zoe is an extremely minor goat character that most people don't even know the name of. But if he hadn't went looking for Legosi right when he did, Legosi would have eaten Haru, resulting in a very, very different story than what we got.
• Dying Breed rarely appear in BECK, but they inspire both Ryuusuke and Koyuki to push the band to great heights, and Eddie Lee's death causes a Heroic BSoD from almost the entire music world. Not only that, but rumors of an unreleased song of theirs drive a huge portion of the plot.
• Berserk has Adonis, the son of Count Julius and cousin to Princess Charlotte. He gets little to no lines and his only purpose is to get killed by Guts, when he ends up seeing his father getting killed by him. But Guts is clearly broken up about killing the kid, which is among the reasons that he decides to leave the Band of Hawks, and Griffith, to pursue his own dream. And that decision ended up influencing Griffith so far that it spiraled out of control and into the events of The Eclipse.
• Case Closed:
  • Narumi Asai was only in one case ("Moonlight Sonata"), but the strong impact it had on Conan/Shinichi cannot be understated. This case haunts Shinichi as the first time he was faced with a suicidal culprit whom he was unable to save.
  • Asami Uchida makes an appearance in one case, but thanks to her, it's now known that Ran is Shinichi's first love.
• Chainsaw Man:
  • Himeno is a supporting character who dies about a quarter-way into Part 1, but her character casts a huge shadow over the rest of the story. Aside from her death establishing very firmly that nobody in the cast is safe and off-limits (a fact that'd have major repercussions in Part 1's closing arcs), Aki's discovery that she cared enough about him to trade her life for his shocks him out of the self-destructive funk that he's in at the beginning of the story and causes him to start opening up to others and take on a protective mentor role for Denji and Power for others the way Himeno once did for him.
  • The US President appears for a few panels, but Gun Devil's second rampage in Japan would not have happened in his desperate effort to kill Makima, the Control Devil. The Gun Devil will also end up killing Aki, possessing him to become the Gun Fiend, and has to be put down by Denji, which starts off his Trauma Conga Line for the rest of the Part.
• Choujin Sensen: Even though Haruna is no more than Love Interest of Tomobiki, it was her that encouraged Tomobiki to search up the [Superhuman Game] online and participate the death match (although Tomobiki didn't exactly expect that his life is on the line). You can say that she's the whole reason why Tomobiki starts to fight for his (somewhat pathetic) life.
• Interestingly enough, despite being the protagonist in Code Geass in the side story Code Geass: Akito the Exiled "Julius Kingsley" aka Lelouch is this. He's only really involved during the third OVA, but without the impact of the Ark Fleet and his coup against the Grand Duke of Euro Britannia, neither Gene Smilas or Shaing could have gotten their plans off the ground so quickly, which resulted in the climax in canon and likely the Earn Your Happy Ending that Akito and co got.
• In Cyberpunk: Edgerunners, Tanaka Sr. is the father of Katsuo, the bully who torments David during the first two episodes. He is also the director of the Cyberskeleton program and, while he's only present for three episodes before he's killed off, his actions — or more specifically his knowledge is what sends Lucy over the edge in her Violently Protective Girlfriend tendencies with David as she finds out he's targeted to be a lab rat for Arasaka due to his tolerance to cybernetics. This leads her to deliberately botch the job (which gets Maine and Dorio killed due to Trauma Team being called) and ultimately leads to David's death as well after she gets caught trying to cover their tracks and David goes out of his way to save her.
• In Danganronpa 3: The End of Hope's Peak High School, Sato and Natsumi Kuzuryu are this to its logical extreme. Both appear for around half an episode, yet Sato's murder of Natsumi and Hajime investigating and then also trying to investigate Sato's murder causes him to meet Juzo Sakakura. Sakakura proceeds to give him a vicious verbal and physical beatdown that breaks his spirit and causes him to go through with the Izuru Kamukura project, which causes Junko to learn of him and eventually cause The End of the World as We Know It. So all of the events of the Danganronpa franchise can be linked back to those two.
• The Dangers in My Heart: Rin Kanaoya ceased having any role in the story at large since exactly 2 chapters from Volume 1 and 2 each, the rare gags and cameos involving her from the rest of the series aside. Nonetheless, her accidentally injuring Yamada in basketball practice is what led to Ichikawa realizing he liked Yamada. Which also led to Ichikawa indirectly consoling Yamada by leaving her tissues in the library, and Yamada starting to actively start conversations with him from then on.
• In Death Note:
  • Lind L. Tailor's brief introduction and death allows L to track Light to the region of Japan he lives in, alongside showing both L and Light what the other is capable of.
  • SPK agent Stephen originally seems like another background character who doesn't accomplish much, except for the finale when it's revealed that Stephen was able to perfectly replicate Mikami's Death Note. This skill causes Mikami to make a mistake that outs Light to Near, leading to Light's death and the final end of Kira's reign of terror.
  • Misa's stalker. He doesn't even have a name in the manga or anime, but if not for him Gelus, a shinigami, wouldn't have died saving Misa's life. And Misa never would've received his Death Note from Rem. Without Misa as the second Kira, most of the story would've played out differently.
• In Demon Slayer: Kimetsu no Yaiba:
  • At the start of the series, Tanjiro is on his way back home from selling charcoal when an old man named Saburo insists that he stay the night at his house, since it's getting dark and demons attack at night. Tanjiro accepts despite not believing in the existence of demons, and this saves him from Muzan Kibutsuji's attack on his family, which resulted in Tanjiro's sister Nezuko being turned into a demon and the rest of the family being killed. Tanjiro's survival sets him on the quest to return his sister to being human, resulting in him becoming a Demon Slayer and The Hero of the story.
  • Kyojuro Rengoku is the first Hashira the main trio are officially drafted on a mission with. Kyojuro dies on that same mission, but he leaves quite the impression on Tanjiro, as a mentor figure and friend; Kyojuro's flaming determination became a part of Tanjiro quite literally, as Kyojuro's original sword guard was preserved and then embedded on Tanjiro's fourth sword in the series. Kyojuro's death is also the first one Inosuke reacts to with proper sorrow.
  • Muzan's doctor from the Heian Period created an experimental elixir that could theoretically cure Muzan's terminal illness, but the latter kills him in a fit of anger and impatience when it didn't appear to work. The elixir worked after all and turned Muzan into the first demon, but because he killed the doctor before the elixir and the treatment could be properly finished, Muzan was left with a crippling weakness to sunlight, leading him to search for the means to overcome his weakness. Despite only appearing for one scene in Muzan's backstory, the entire plot of the series would never have happened if the doctor had not given Muzan the elixir in the first place.
• Digimon Tamers:
  • IceDevimon was a Monster of the Week who kidnapped Rika with the intent of making her his Tamer. While he was destroyed at the end of his episode, Rika's encounter with him was so traumatizing that she declared her hatred of all Digimon including her own partner Renamon. She and Renamon wouldn't reunite until an episode later, which was the beginning of a massive change in Rika's attitude towards Renamon and Digimon as a whole.
  • The Horse Deva, Indramon, only appeared in two episodes, the second of which was his death. However, his vicious beatdown on Impmon set in motion the events that led to Impmon making a deal with the Devas to become Beezlemon, which in turn led to the death of Leomon and Jeri becoming susceptible to the D-Reaper.
• Dragon Ball:
  • Grandpa Gohan is dead by the original Dragon Ball's beginning and only appears in person during the Fortuneteller Baba Saga, but it was his finding Goku and raising him that turned Goku from the future destroyer of humanity to the altruistic All-Loving Hero we know and love. Furthermore, Goku's first born son is named in his honor.
  • Believe it or not, Raditz is essentially the catalyst for the entire second half of the Dragon Ball manga (or Dragon Ball Z, as it's usually named). Had Raditz not remembered his little brother and come to Earth, the entire series would have been turned on its head: Piccolo and Goku would never have teamed up and thus Piccolo wouldn't have joined the Z-Fighters. He may have even remained evil, and continued on with a plan to terrorize planet Earth, had he and Goku not joined forces. Goku wouldn't have trained with King Kai, but merely at his own pace, and would have been far too weak to combat the androids by the time they arrived, assuming he hadn't already died from the heart virus he was to contract. Gohan would never have been trained by Piccolo, and thus would never have become a fighter at all. Vegeta and Nappa would never have received the transmission involving the Dragon Balls, and thus would never have visited the Earth, thus remaining under Freeza's thumb — Freeza himself would also never have been killed, allowing the Cold family to continue terrorizing the universe. And who knows what trouble Babidi would've caused if he'd arrived earlier and unleashed Buu unchallenged. Despite being the weakest villain at the start of the series, Raditz coming to Earth is what allowed the Z series to be what it became.
  • Dr. Gero. He's long dead in Trunks' timeline and is only around for a few chapters/episodes as Android 20 before being killed by Android 17. However, it is Gero who created all the androids, including Cell, and his actions turns two timelines into a living hell and nearly destroys the solar system of the main timeline. Literally everything bad that happens in the Android/Cell Saga is his fault.
    • Gero is also an example of Remember the New Guy?. He is a member of the Red Ribbon Army, a major villains faction from the original Dragon Ball series and was the creator of Android 8, the first successfully created Red Ribbon android and the first one the heroes faced. However, Gero wasn't seen or mentioned until the Android Saga years later in real life.
    • And then in Dragon Ball Super, even though Gero's creations aren't actually involved, the entire Future Trunks saga where Goku Black and Zamasu wreak havoc on the future timeline was caused because Bulma invented time travel to undo the damage left behind by the Cyborgs/Androids. And on the bright side, Dr. Gero also indirectly saved the multiverse by creating Androids 17 and 18, who were key players in the Universe Survival tournament, with the former ending up the ultimate victor and passing the Secret Test of Character behind the tournament by wishing for the others' return.
  • Bibidi is long dead by the time the Buu saga begins, and only a late anime flashback shows what he even looks like, but he's the one who instigated it by summoning Majin Buu in the first place. And while his 'son'/doppelganger Babidi is continuing the plan in his place, Babidi doesn't have all of Bibidi's knowledge, and so doesn't know the spell that actually unseals Buu, forcing him to steal energy to do it. Babidi is also verbally abusive to Buu and controls him through the threat of being sealed away, unlike Bibidi who preferred to use cake as a reward, which got him killed when Buu finally made it clear that he didn't appreciate the poor treatment.
  • Van Zant, the Ax-Crazy gunman who shot Mr. Satan and Bee, triggers the latter half of the Buu Saga. He only appears in two episodes, and isn't even named in the manga, but his attack on Mr. Satan and Bee, whom Majin Buu had befriended, directly results in the creation of Evil Buu, who in turn eats his good half and becomes Super Buu.
  • The Yardrat race barely appears in the anime and not at all in the manga, but them teaching Goku Instant Transmission off-screen ends up saving the earth several times over.
  • Similarly, the Metamoran race never shows up, even in the anime, but they taught Goku the Trope Namer for Fusion Dance, which he passes on to Goten and Trunks.
  • As of Dragon Ball Minus and Dragon Ball Super: Broly, Bardock and Gine. They were the ones to send Goku to Earth. If they hadn't, Goku would have died along with their planet. And without Goku, Pilaf would've become ruler of earth thanks to the Dragon Balls.
  • Lord Zuno, the smartest being in the universe; despite him showing up for only two scenes in the Future Trunks Saga, it's him telling Zamasu about the Super Dragon Balls and Goku that gives Zamasu the information needed to begin his plans, first by killing his master to become a Supreme Kai and taking the Time Ring, using it to go a year into the future, and making a wish on the Super Dragon Balls to take Goku's body, creating Goku Black.
  • In Dragon Ball Super, the three muggers who try to rob Goku unknowingly cause the Universe Survival arc.
• Elfen Lied:
  • Tomoo appears in one episode and one manga chapter, but it was his actions that ultimately played the biggest role in turning Lucy into a bitter figure who hated humanity (namely he beat her puppy to death with a rock/vase and made Lucy watch when he did). Lucy snapped and brutally executed him and his cronies, as well as someone who may or may not have meant to betray her. It was all downhill from there.
  • Speaking of someone who may or may not have meant to betray Lucy, the unnamed "orphanage girl" also has a small role, but has just as big an impact on the plot as Tomoo: the reason Tomoo found out that Lucy even had a puppy was because the orphanage girl told him about it, even though the orphanage girl had previously promised Lucy to keep the puppy's existence a secret. So while Tomoo's murder of a puppy sent Lucy down the path of misanthropy, it was the unnamed orphanage girl who made Tomoo's actions possible. The girl later claims that she blabbed about the puppy by accident, but Lucy thinks the girl betrayed her on purpose out of malice. It's left ambiguous which interpretation is correct.
  • Aiko Takada has an equally brief appearance, but she's Lucy's second human friend, and it was her death that resulted in Lucy being captured and imprisoned in the Diclonius Research Institute, as well as the catalyst for Lucy's long-running vendetta with Kurama.
  • Diclonius Silpleit # 3 died quickly in a flashback, but not before infecting Kurama and his original assistant with the virus that caused their children to be born Diclonius. This led to Mariko's birth, the realization of the manner of Diclonius propagation, and down the line, the existence of Lucy.
• Fly Me to the Moon has Iwakasa, a subordinate of the Emperor in Princess Kaguya's time and Tsukasa's father. The Emperor told him to burn the immortality-granting Hourai Elixir, but instead, Iwakasa gave it to his daughter, resulting in Tsukasa becoming immortal, thereby living long enough to meet Nasa. Because of him, the entire plot became possible.
• Kyoko Honda from Fruits Basket is a Posthumous Character when the story begins and she only appears during flashbacks, but her influence is felt through her daughter Tohru's idealism and a few other characters she helped before she died. Her death is also what essentially kicks off the plot, as Tohru would likely never have become involved with the Sohma clan otherwise.
• Fullmetal Alchemist:
  • Nina Tucker clearly plays a very significant role in the Elric brothers' lives for someone who died so early in their career. Being forcibly fused with her dog Alexander into a tortured chimera, as well as being Mercy Killed by Scar, becomes a major part of Ed and Al's Character Development that shape how they develop and view alchemy. Additionally, the element she was connected to, chimeras, comes up again and again in the series.
  • Shou Tucker, the father of the aforementioned Nina, only lasts for one chapter before being killed by Scar. However, his act of fusing Nina and Alexander into a tortured chimera shows both the Elric brothers and the audience the kind of depravity alchemists are capable of, with the brothers' inability to save Nina haunting them for the rest of the series and motivating them to make sure no one else suffers as she did. In addition, his work in creating a talking chimera would later be used to create human-animal chimeras that would become important later on in the story.
  • Van Hohenheim's master and the King of Xerxes are already long dead by the time the story begins^note And in the latter's case, he is only brought back to life in an unstable body before Father kills him. and aren't even given names, but they both play an important role in the backstory of Hohenheim and Father that would set the plot in motion. Hohenheim's master and alchemy teacher would create the homunculus that would become Father from Hohenheim's blood, and the King of Xerxes, in his desperation for immortality, would be manipulated by the homunculus into creating a transmutation circle that would sacrifice the population of Xerxes and trap their souls within Hohenheim and the homunculus, granting them immortality and also allowing the latter to create a body for himself that looks identical to Hohenheim.
• Gundam:
  • Gene in Mobile Suit Gundam. He's a random Zeon Mook killed in the first episode, but his decision to disobey orders and attack the Project V mobile suits is what causes Amuro to hijack the Gundam and consequently set off much of the UC in motion.
  • Crank Zent in Mobile Suit Gundam: Iron-Blooded Orphans. He's a Gjallarhorn officer who refused to harm the children in CGS base and was mercy killed by Mikazuki in the third episode, but his death was the driving force of Ein Dalton's vow on "absolving" the sinful children who killed Crank.
  • Eve in Gundam Build Divers Re:RISE. She only shows up in flashbacks, implied to be dead at the start and and her name is only listed on the series' Japanese webpage. But, her existence is what drives Hiroto throughout Season 1 of the series and gives meaning to his Gunpla's armor system.
• Hayate's parents in Hayate the Combat Butler, who only appear a few times in flashbacks at least until the very end of the manga and don't even have faces, but their monstrous negligence and abuse of Hayate is ultimately what turned him into a Broken Ace, and both directly led to him meeting Athena and thus learning all of his combat skills and eventually trying to kidnap Nagi, which then led to him becoming her butler.
• Hello Sandybelle: Had Luzanne not portrayed Mark's paintings in public, Mark would have never won the grand prize at the European Grand Prix and climbed out of his poverty.
• In Hinamatsuri, Atsushi is a background character, but the existence of the Bad Future Hina and friends comes from depends on whether he reunites with his old bandmates and gets back into music or not. The last major arc in the manga is all about the girls managing to get him to rediscover his old passion for music so they can live a peaceful life.
• I Belong to the Baddest Girl at School: Tsukaji is a very minor character, yet she's the catalyst for Kanade giving up her position as Banchou for a time.
• InuYasha:
  • The dark priestess Tsubaki is only around for five episodes, and appears in flashbacks in two more, but she is the one who placed the curse on Kikyo which ended up weakening her spiritual powers, leaving her vulnerable to Naraku's attack which led to her death and Inuyasha being framed and pinned to a tree for fifty years.
  • The demon necromancer Urasue is only around for two episodes, but she has quite the impact on the series, having been the one to resurrect Kikyo.
  • The moth demon bandit Gatenmaru only appears in two episodes as well, but he forces Inuyasha into his Superpowered Evil Side, resulting in his death and the deaths of quite a few of his human minions; it's this incident that finally convinces Inuyasha to give up his plan of using the Shikon Jewel to become a full-fledged demon.
• Admiral Robert J. Hanner, United Planets Space Force (ret.), from Irresponsible Captain Tylor appears only about four times in the 26 episode series, and only once in a speaking role. However, directly or indirectly, he's responsible for Tylor becoming a starship captain, the Soyokaze crew getting demoted, the war with the Raalgon being able to conclude without additional bloodshed, and his death sparks a Heroic BSoD from Tylor.
• JoJo's Bizarre Adventure:
  • A petty thief named Dario Brando abused his only son and treated him like crap. Imagine for a second; if this petty pick-pocket, a nobody in the grand scheme of the universe, had instead been a Doting Parent who worked hard and treated his family with kindness all his life, Dio Brando, The Tyrant who remade The World, would have grown up to be just another honest yet equally faceless laborman in Victorian London, and more importantly; the Joestar/Kujo family's legacy as Warriors and Heroes would never have been awakened without him finding George, accidentally saving his life, which in turn led to Dio's vicious bullying of Jonathan in childhood. Like-father Like-Son, after all. Though, even if the Joestar/Kujo's legacy would never awaken, no threats would come to the world because Dio would grew as a honest man.
  • An even more extreme example would be the nameless vagrant who harassed Dio and became the first victim of the Stone Mask. His transformation into a vampire was what gave Dio the idea to use it on himself, and subsequently become an immortal menace who haunted the entire Joestar line.
  • After the battle against Dio ended, a nameless vampire managed to escape detection, and became an officer in the British air force. He killed George "Jorge" Joestar II- Jonathan's son and Joseph's father — when George uncovered is identity, and while George's widow Elizabeth was able to kill him, it resulted in her being wanted as a murderer and having to go into hiding as Lisa Lisa. Because of one minor character who's dead by the start of Part 2, Joseph never knew his parents for much of his childhood.
  • Gray Fly is the Starter Villain of Part 3, who attacks the protagonists while they're on a plane out of Japan, and he is never mentioned after his defeat. However, were it not for him, the epic quest across multiple countries that makes up the bulk of the story would have been reduced to a mere plane flight and ended in a few days. The reason is because his actions caused the plane to crash and endangered the lives of the passengers, the protagonists realize that they can't risk getting civilians caught up in their battles, even it forces them to take a longer route to Egypt.
  • Enyaba appears for a few scenes in Part 3 and is killed by DIO in her first major appearance. She is also the reason DIO managed to awake his Stand, The World, thanks to her buying the Stand Arrows from an Italian mafia boss (As revealed in Part 5), and it's heavily implied that much of DIO's knowledge of the Stand phenomenon come from her teachings, meaning that if it wasn't for Enya, DIO and none of the Joestars would have awakened their Stands, and DIO wouldn't have known about "heaven", meaning that she is the main reason for the Downer Ending of Part 6. Which is pretty impressive, as she was only a Climax Boss.
  • The lives of the protagonists of Parts 4 and 5 were each greatly influenced by an unnamed person who only appears as a part of their flashback, whose face isn't even properly seen. For Josuke, it was the man who saved his life when he was sick in the snow, who he felt so indebted to that he models his hairstyle after that of his saviors. For Giorno, he saved the life of a gangster by keeping his lips sealed and was rewarded with kindness by the man, which made Giorno realize the potential of the mafia to help people, which inspired Giorno to be like him.
  • Leaky-Eye Luka in Part 5. He only appears for one chapter, has no stand ability, and pretty much defeats himself, but his death is what causes Bucciarati to track down Giorno, resulting in the plot between the two of them to take over and reform Passione that drives the rest of the storyline.
  • Similarly in Part 5, Polpo appears in only two scenes (his own stand has more page-time than him), but his death drives the plot just as much as Luka's, both in the revelation that he had a massive treasure hoard hidden away (that Bucciarati uses to boost themselves to Operator status) and the revelation that he was responsible for protecting Trish, the daughter of The Don of Passione. After his death, Bucciarati and his team are tasked with protecting Trish.
  • Weather Report's mother in Part 6. She swapped Weather from his parents and elder twin brother Enrico Pucci in the crib with her still-born baby, leading to Pucci picking the path to priesthood. Weather and Perla Pucci began eventually dating without being aware of his true parentage, which Pucci found out when the said woman confessed to the incident. Pucci will then try to break the couple up to avoid Brother–Sister Incest, leading to Pucci hiring a private detective to do so. Unknown to him, the detective was a part of Ku Klux Klan, who promptly tried to kill Weather and hang him. Witnessing it and thinking that Weather's dead, Perla commits suicide which caused Pucci to fall into despair and join DIO and Weather unleashing Heavy Weather and then losing his memories and thrown into prison. In short, if not for her actions, Part 6 would have been completely different.
• Jujutsu Kaisen:
  • Setsuko Sasaki, the president of the fledging Occult Club of Yuji Itadori's school may have vanished from the plot after the Introduction Arc, but her attempting to unseal one of Sukuna's fingers is what kickstarted the plot.
  • Junpei Yoshino, who ultimately has a minor role in the story due to getting killed by Mahito unwittingly makes Yuji a fierce arch-enemy of Mahito, an enmity which lasts even unto a major battle of the Jujutsu sorcerers, and makes him rely on Sukuna less due to him laughing at his death.
  • Riko Amanai, who is a Posthumous Character due to being killed by Toji, ultimately is the main reason for the Face–Heel Turn of Suguru Geto from a moderate Sorcerer to the genocidal supremacist we see him as in 0, resulting in his death and Kenjaku possessing him for his ability. Due to her death, Tengen is unable to merge with a Star Plasma Vessel, thus turning into a Curse, whom Kenjaku plans to use for his own nefarious deeds.
• Kagerou Project: Tsukihiko, Azami's husband, appears very briefly in the anime, and in only one of the music PVs, yet his love and acceptance of Azami was what led her to develop her own emotions, resulting in the creation of the Heat Haze World and the Favouring Eyes Snake, born of her love for her husband and child, and the snake that is the key to saving everyone. Azami herself could count, as she is the source of the main cast's powers and the grandmother of Marry, and she appears nearly as little as her husband does.
• Kaguya-sama: Love Is War:
  • The Mass Media Club president only shows up twice before graduation, and the only time she actually does something is during a flashback where she falls in a swamp and nearly drowns. Despite this, she has a major influence on the overall story since Kaguya rescuing her is what caused Shirogane to fall in love in the first place. She has a slightly larger presence in the We Want to Talk About Kaguya spin-off (as the main characters there are both members of her club), but she still mostly stays in the background.
  • Ogino only shows up in 3 chapters (and all those appearances are in flashbacks), but he's single-handedly responsible for turning Ishigami into the person he was at the beginning of the manga.
  • The previous Student Council President also never shows up outside of flashbacks (barring an Early-Bird Cameo in episode 17 of the anime and a brief scene during the seniors' graduation), yet his actions led to the story's two longest ongoing plotlines. Shirogane never would have fallen in love with Kaguya if he hadn't reached out to him and taken him to the swamp the Mass Media Club president fell in on that fateful day, and Tsubasa never would have confessed to Kashiwagi if he hadn't established the practice of allowing students to seek advice from the Student Council.
  • Toyomi Fujiwara's appearances in the series are mostly limited to cameos and she almost never interacts with anyone other than her little sisters. However, one of the fanbooks revealed that she tutored Shirogane back when he was in elementary school, meaning she is partially responsible for his insane study habits that both led to him getting into Shuchi'in in the first place and got Kaguya to actually pay attention to him back during her Ice Queen days.
  • Momo Ryuju's actions in the plot are mostly relegated to brief references, but the one big thing she does is encourage Shirogane to attract Kaguya by acting as an academic rival, directly setting in motion the Duel of Seduction that defines the first half of the series.
  • Shirogane's mother only ever shows up in a few flashbacks plus a single physical apperance in the final volume, but the shadow she casts over her family (especially her son) has massive repercussions over the course of the series.
• Nanami's father from Kamisama Kiss only appears in the first chapter and a few flashbacks, but it's him running away to escape his gambling debt that leads to Nanami becoming homeless and accepting a strange man's offer of giving her his home. The home turned out to be a shrine, and by giving it to her, he made her the new kami. The plot is about her dealing with this position.
• Kiki's Delivery Service has Madame's granddaughter who is notable for being a Rich Bitch and a Foil against the much kinder grandmother. She is such a brat that she inspires Kiki's bad mood, which mixed with a long, miserable flight home during a heavy downpour of rain results in her being too unhappy to go to Tombo's party and getting sick the next day. Later on, the granddaughter's reappearance as one of Tombo's acquaintances during Kiki and Tombo's outing sours Kiki's relationship with Tombo and also causes her to lose her powers.
• Komi Can't Communicate implies that this is the case for Gorimi Senpai. It's hinted that Agari being her understudy library chief is why Agari has gained some agency and self-esteem.
  • Ai doesn't show up much, yet it's partly because of her constant bullying that Makoto is both super buff and super shy.
  • If Seikimatsu Toshio hadn't elbowed Tadano unconscious in Chapter 4, Komi wouldn't have stayed behind in the classroom or had the conversation that lead to Tadano becoming her first friend. Yet Seikimatsu makes very few appearances in the story.
  • Kawai has only been mentioned a couple of times, but her rejection of Tadano's confession in middle school became the root of his habit of "reading the room"; more to the point, it shook him out of his chuuni phase, turning him into the Ridiculously Average Guy he is today.
• Lyrical Nanoha:
  • The Number Due from Magical Girl Lyrical Nanoha StrikerS. Despite being the most minor of the twelve Numbers, she's responsible how the Big Bad Jail Scaglietti got Olivie Sägebrecht's DNA and could create the Sankt Kaiser's clone Vivio Takamachi, who is the Vessel of the Saint's Cradle and the main character of ViVid. Due was Quattro's mentor, the most vicious of Scaglietti's three Co-Dragons, who inherited many traits of Due's psyche and personal ambitions as a result of the time that they spent together. She also provides Bad Guys Do the Dirty Work by killing the TSAB High Council and Regius Gaiz, which goes a long way towards making sure the Bureau doesn't repeat their mistakes.
  • The three unnamed girls who bullied Rinne in ViVid Strike! only show up during a single episode in a flashback, but literally every bad thing that happens during the season proper (save for Fuka being fired from her job) can be directly traced back to them since pretty much all of Rinne's actions are influenced by the emotional scars they left on her.
• Maria no Danzai: Kiritaka Nagare only appeared in the first chapter, where he was killed, but he was a significant focus in the first chapter. But his death kickstarts his mother, swearing vengeance on all the bullies for how they treated and killed him. It was revealed that he had a loving relationship with his mother, Mari, and was horribly bullied by satanic thugs at his school. Eventually, he was killed in a prank gone wrong, and his mother unfortunately witnessed his death. Kiritaka Nagare's death influenced the entire story; after an investigation where the police told his parents that he committed suicide because of abusive parents, Mari discovered his journal and found the truth that bullies tortured him at his school, and he was gathering evidence to turn them in. Mari snapped and swore revenge on the bullies, saying that revenge was too soft and that she would give them judgment. Mari threw away her life, divorced her husband, changed her name to Maria Akeboshi, had plastic surgery, and two years later became the nurse at the bullies' school to exact revenge.
• Gai Daigouji in Martian Successor Nadesico, a Sacrificial Lion only lasts for 3 episodes before dying a tragically ignoble death. His death, however, has a lasting impact on main character Akito, and he's the guy who introduces Gekiganger 3 to the crew of the Nadesico, which becomes very important when it turns out that the "Jovian lizards" have based their entire culture around it.
• The bandit from Miss Kobayashi's Dragon Maid. She only shows up in a single chapter as part of a flashback and isn't even given a name, but meeting her changed Tohru's entire world view and is a big part of the reason why Tohru became Kobayashi's maid.
• Monster: Director Udo Heinemann is among the first batch of murder victims in the story, but it's because of how he operated as Tenma's boss at Eisler Memorial Hospital that Tenma had a change of heart in time to unwittingly save the life of the titular Monster.
• My Hero Academia:
  • The Sludge Villain from early on in the series is such a Starter Villain that he doesn't even get a proper name in the story, yet his role is crucial, allowing the protagonist, Izuku Midoriya, to meet his idol as well as inherit his superpowers, in addition to providing an initial wake-up call for Bakugo that he's not as big a badass as he thinks he is.
  • Stain, the Hero Killer, while a fan-favorite and a massive Knight of Cerebus, was still ultimately an Arc Villain, who was defeated in his first on-screen battle before being sent to Tartarus Prison for the rest of the series. However, his impact on the story and setting were massive, having inspired dozens of new villains with his philosophy. Of those he inspired, many, like Toga and Dabi, would join Shigaraki's League Of Villains due to the misconception that he was a member of the League, something that Shigaraki capitalized on. Allowing them to become prominent recurring villains. What's more, the intensity of his beliefs were what drove Shigaraki to develop a solid philosophy and goals of his own, which was when he started growing out his Psychopathic Man Child tendencies, and into a much more dangerous villain. And all of this was caused solely by Stain's reputation.
  • The Chainsaw Nomu that appears in the Training Camp arc, who chases Yaoyorozu and Awase around a bit, and then leaves. But before he does, the two are able to attach a tracking device to him, leading the heroes right to the Nomu Factory, which in turn sets up events with ramifications throughout the rest of the story.
  • Kotaro Shimura is a Posthumous Character, but his influence can be felt in the whole manga, as his treatment turned his son Tenko Shimura from a sweet child alongside All For One into the Big Bad Tomura Shigaraki.
  • The Fourth Torchbearer of One for All, Hikage Shinomori. He only shows up along with the other Torchbearers in Izuku's mindscape, and never fought All for One, yet his contribution to One for All's power is the greatest (only behind All Might), having held onto it for eighteen years before passing it to Daigoro Banjo. This not only granted it the extra power that would later allow All Might to defeat All for One, it also let him and the other Torchbearers discover later on that One for All was a Deadly Upgrade that would Life Drain people with Quirks.
  • The "Ordinary Woman" (or "Ippan Josei" in Japanese), is a minor character with a Mutant Quirk that makes her nearly 10 feet tall and resembles a mix between a shark and fox. She is introduced late in the series with at least 3 chapters and a couple of cameo appearances under her, when hero morale has hit an all-time low and villains have been broken out of prison. While Fantastic Racism against "Heteromorphs" has been an ongoing discussion in the series and sometimes in varying degrees, her role as a victim of and unexpected player against it leaves a big impact in some fashion.
    • Support for heroes gets so bad, she was attacked by vigilantes who took matters into their own hands but mistake her for a villain herself, blaming her heteromorph appearance when Midoriya steps in to save her. He asks All Might to take her to a nearby shelter, but she is among the others that have been turned away by many because of their appearance. When she is let into U.A, she meets Deku again and thanks him for what he did for her.
    • During the final battle throughout Japan, when members of the Paranormal Liberation Front send a message out to all heteromorphs to form an attack mob led by Spinner at a hospital, she passes this message along students Shoji and Koda who join teachers Aizawa and Yamada to help stop it. While it was revealed to be a scheme to free League of Villains' Kurogiri, Shoji (who had suffered his own form of racism years ago) wants to stop it before it makes people's view of all Heteromorphs even worse.
• John Smith has two scenes in twenty-six episodes of My-HiME. He tells Natsuki her mother was planning to sell her to Searrs, which causes her Psychosomatic Superpower Outage, which leaves her vulnerable to Nao, which puts her in Shizuru's care, which causes Shizuru to give in to temptation and kiss Natsuki unawares, which Haruka and Yukino witness, which leads to Shizuru's breakdown, which leads to the utter slaughter of District One. That was just the result of Smith's first scene. For his second, he tells The Obsidian Prince about the Vortex weapon that Saeko Kuga developed for Miyu, causing Mikoto to get sicced on Midori, which results in her defeat and the death of her most important person.
• Naruto:
  • Rin Nohara, as her death caused a major villain's Start of Darkness, and by extension nearly every significant event in the plot.
  • Sasuke in The Last. He may have been Demoted to Extra, but if he hadn't arrived in Konoha when he did with Hiashi in tow, then the Hokage Monument would have been reduced to dust, Kakashi and countless others would have been killed and the Raikage would have blown up the moon, killing Naruto and co.
  • Iruka, Naruto's teacher at the Academy, doesn't really have much to do with the series' action. But if it wasn't for his faith that Naruto was a good person and not the Kyuubi reborn, Naruto might well have turned out as Ax-Crazy as Gaara from the All of the Other Reindeer treatment he recieved all his childhood. And it was because of Iruka's teaching and example that Naruto decided to try to befriend the Kyuubi.
  • Zabuza and Haku were the Starter Villains of the series, appearing during the first proper story arc, when the manga's chapters were still in the low double digits, and dying only 15-20 chapters later. Yet, they still had a profound impact on Naruto and inspired him to create his own philosophy that rejected the concept of ninjas as tools, and instead emphasized their existence as human beings... Essentially, if it hadn't been for Zabuza and Haku, Naruto would never have become the Messianic Archetype he eventually turned into. This is much later acknowledged in-series by Kakashi who informs the resurrected Zabuza and Haku that Naruto found his own path in life thanks to them, and Kakashi himself expresses gratitude that they were Naruto's first opponents.
  • Mizuki is an extremely minor villain that only appears in the first chapter and permanently disappears from the manga afterwards, but were it not for him, Naruto would've never taken the Scroll of Seals from which he learned the Shadow Clone technique, which he uses throughout the series. Also, if not for Mizuki's actions, Iruka would never have assured Naruto that he's a good person, thus indirectly saving the world.
  • Aoba Yamashiro is a minor Konoha jonin who blabs about Itachi's return to Konoha within earshot of Sasuke. Sasuke would run off for revenge, suffer a Curb-Stomp Battle, and question the value of the village's training. Put simply, the Sasuke retrieval plot and the entire second half of the manga can be traced back to an otherwise inconsequential man carelessly running his mouth.
  • Rasa, the fourth Kazekage and Gaara's father, doesn't appear in the manga as himself until "Shippuden", but he was the one responsible for Shukaku being transferred to Gaara as a desperate measure to prop the Hidden Sand, thus the village fearing him. Rasa then manipulated Yashamaru to kill Gaara due to deeming him a failure, resulting in Gaara snapping and becoming a ruthless serial killer until Naruto managed to redeem him.
• Kaworu Nagisa from Neon Genesis Evangelion. Despite only appearing in one episode, he serves major plot relevance as the final angel, has a prominent role in Shinji's development as a character, and has some of the most poignant scenes in the entire series.
• In One Piece:
  • A minor Marine character named Shu who, despite appearing in only one manga chapter/anime episode, managed to actually destroy one of Zoro's swords thanks to his Rust-Rust Fruit powers. Not only did he rust up the sword that Zoro personally received from a man who respected him, but Zoro ends up using two swords for awhile until he finally gets a permanent replacement in the middle of the Thriller Bark arc.
  • The unnamed mook of Caesar Clown who sent the distress signal after being attacked by Kinemon to Luffy doesn't even appear, but he indirectly manages to bust Caesar Clown, remove Doflamingo from power by exposing his nefarious deeds, cause Law's defection from the Seven Warlords, save Zou and Wano from Kaido's people, set Luffy on the right path to Laugh Tale, make the World Government do away with the Seven Warlords System and start the Great Pirate War. Big impact indeed.
  • Vinsmoke Sora is a minor character from the North Blue who's long dead by the time of the story and only interacts with one of the main characters. But her actions indirectly saved the Straw Hats several times over. She's Sanji's mother, if she hadn't taken a dangerous drug to reverse the gene surgery on Sanji, he would have turned out like his brothers — superpowerful, but completely lacking in empathy and would never have joined the Straw Hats.
  • Captain Nezumi, a corrupt Marine only present for the Arlong arc, is the reason that Luffy received a bounty in the first place. Without him it may have taken longer to earn, if not just having been a far less eyecatching thirty-million at the start.
  • Streusen is one of dozens of Big Mom affiliated characters introduced in the Totto Land arc, and not one of the ones to get into a major fight and appeared in only a few panels. He still is the reason that there is in fact a Big Mom in the first place, having been the one to 'guide' a six-year old but still terribly powerful Charlotte Linlin into becoming a pirate and terror in the first place. Essentially anything to do with Big Mom's actions, be they from her dozens of children to her time in the Rocks Pirates that in turn led to Kaido getting his Devil Fruit, is all because of him.
• Ōoku: The Inner Chambers:
  • Lady Matsu only appeared a couple times but her death is the catalyst for all the chaos of Tsunayoshi's latter reign, and by extension the rest of the Tokugawa shoguanate.
  • Saigo Takamori only appeared in the final volume, but ultimately it was his decision to cover up the fact that the Tokugawa shoguns were (mostly) women and spare Edo from destruction (albeit after some blackmail from Chikako).
• Ai Hoshino from Oshi no Ko; despite being the face of the series in promotional materials, her children Aqua and Ruby are the real main characters, and she's only around for the first nine chapters of the manga and the first episode of the anime, after which she's murdered. However, her presence still hangs over the rest of the narrative, and finding the man who organized her death is Aqua's primary motivation.
• Hibari and Hikari from Penguindrum. For a long time, their only appearances were in the background on advertisements and in the ending credits, and then they showed up briefly in a backstory episode to give some insight into Himari's past. However, they end up being absolutely integral to the ending when they show up for less than five minutes in the final episode to drop off their new album, which holds Himari's favourite phrase and the fate-transfer spell that allows her to live.
• Meowsie, a female Meowth that Team Rocket's was smitten by only appears in person in one episode of Pokémon: The Series (besides a handful of Imagine Spots by the latter), though she is the entire reason that Meowth is sapient in the first place. Meowsie was unimpressed by a normal stray Meowth, so he learns to speak and act human to impress her. He didn't quite understand that Meowsie was a spoiled cat impressed by riches and spoils, and so she still only snubbed him. Heartbroken, Meowth then joined Team Rocket in hopes of achieving some street cred to impress her instead. Within the show's present day, Meowth met Meowsie again only once (in "Go West Young Meowth"), where it was revealed she was a stray and thus Meowth's talents could be useful to her needs.
• Lord Asano is never actually seen in Princess Mononoke, but those are his samurai who are dangerously close to conquering Iron Town, and it may also have been his men that Ashitaka saw brutalizing the countryside before.
• Enrico, Massimo, and Federico of Reborn! (2004) were the sons of the 9th and the previous Vongola members in line for the role of 10th, with Federico in particular being the favored son. Their influence amounted to little more than footnotes in the first chapter explaining how they died, and they've never been mentioned since. Had it not been for their untimely deaths, the family wouldn't have gone searching for the closest genetic link possible and ending up at wimpy Tsunayoshi's house, Tsuna wouldn't have learned about his family's ties to the Vongola, nobody would have gotten the strength to properly fight off the Kokuyo Gang, Xanxus might have gone through with his strong-arming and ruthless regime, the Millefiore family would definitely have wiped the Vongola out in 10 years, there wouldn't have been potential allies through the Simon family, the Arcobaleno curse would have remained on the tutors with no end in sight, and most importantly, they wouldn't have gotten the candidate whose ideals and friends match the founding lineup of the Vongola itself and set the family on the path that led them back to its former glory.
• Revolutionary Girl Utena:
  • Wakaba is a fairly minor character despite being Utena's best friend, but her crush on Saionji essentially kicks off the plot; she sends Saionji a love letter and he mocks her by putting it on display for the whole school, which prompts Utena to come to Wakaba's defense and starts her involvement with the duels for the Rose Bride.
  • Mrs. Ohtori, the mother of Akio's fiance Kanae and the wife to the actual chairman of the board at Ohtori Academy. She has less than a minute of screen time but every single thing about her ties into all the overall themes of the series. There's even a website which analyzes the symbolism within her first and only appearance, called Mother Dearest.
• Saint Seiya: Sagitta Ptolemy is just another Silver Saint who shows up for a few minutes and easily dies at the hands of Seiya. But not before he embeds one of his arrows in Saori/Athena's heart, giving her only 12 hours to live unless someone shines the light of her shield on her. It so happens that the shield is located at the top of the Sanctuary and Saori's Bronze Saints have to fight the phenomenally powerful Gold Saints to get to it. That's 30-plus episodes of struggling that never would've happened had the mook Ptolemy not done what he did, as the Gold Saints would have just stood to attention if they had met Saori.f
• Take Responsibility For My Stomach has Ritsu and Ruka's kohai from the track and field team. The two are never given names and only appear in the final chapter, but their decision to visit their sempais at college prompts Ruka to lose weight for the sake of her dignity, thereby helping establish the Series Goal.
• A Timid Woman Longing For Her Delivery Girl has Kazama, who only appears in Takase's flashback at her last job, and has a grand total of four lines of dialogue, but his sexually harassing Takase is one of the most important events in the plot. Kazama got fired for his actions, but as a result of that, Takase's coworkers gossiped about her behind her back, blaming her for what happened to him and hoping that she would get fired. This included Aida, who appeared to be a trustworthy sempai to Takase, and Aida backstabbing Takase fueled her trust issues. Traumatized and not wanting to be around others, Takase quit and became a freelancer, a job that allowed her to meet and fall in love with delivery girl Rinko Komine.
• Ukina from Tokyo Ghoul. Her existence heavily influences the plot of the series, though she only appears in a handful of flashbacks and little is known about her. An undercover reporter that fell in love with a young Yoshimura, she gave birth to a Half-Human Hybrid while working on investigating V. When she was found out, his superiors forced Yoshimura to kill her as punishment... leading him to retire, and hide their child elsewhere. Yoshimura took control of the 20th Ward, seeking to foster peace between humans and ghouls — taking in Kaneki after his surgery. On the other hand, her journal drove Eto Yoshimura/Sen Takatsuki to seek revenge for her mother... first as the One-Eyed Owl, and later as the founder of Aogiri.
• The evil alien prince Lacospo in To Love Ru that hired Yami to assassinate Rito. He only has one episode in the anime, and even less of a presence in the manga, only appearing in a cameo or two, but without him Yami, and later Mea and Nemesis would never have come to Earth.
• Yo-kai Watch: Shadowside - The Return of the Oni King: Azure Dragon and his Kindred Yo-kai only appear in the movie for a few seconds, but if they hadn't destroyed Rasen's armor, the heroes wouldn't have been able to finish the job.
• Yu-Gi-Oh!:
  • Pegasus's wife Cyndia/Cecilia died young and her death served as a direct motivator for the Duelist Kingdom (as Pegasus wanted to take over Kaiba Corporation to use its technology to see and touch her again), as well as motivation for Pegasus to create the Duel Monsters game, thus indirectly contributing to the remaining arcs in the series and bringing about the other spinoffs.
  • Mr Ishtar, Marik and Ishizu's father. He is long dead before Battle City but his abusive treatment of his family and obsession with protecting the Pharoah's tomb above his own family is what led to the creation of Dark Marik.
  • The Rare Hunter doesn't even have an in-show name^note given the name "Seeker" in one of the video games and is in-universe considered a little more than a mook that Yugi effortlessly defeats but it was his defeat of Jonouchi/Joey that demonstrated how dangerous the Ghouls/Rare Hunters were and they have much better access to rare cards. He also serves to help kick off Jonouchi's arc by showing the gap between him and Yugi and sets Jonouchi off to improve himself. Also, because Yugi won back Jonouchi's Red Eyes Black Dragon from the Rare Hunter and Jonouchi refused to take it back until he became a worthy duelist, Yugi would be able to use the Red Eyes in his later duel to awaken the brainwashed Jonouchi.
• Yu-Gi-Oh! GX has Bronn, a Duel Spirit who appears in only two episodes of the third season and has any influence on the plot for a relatively small part of said season without appearing. In that time he duels Jaden and loses. However in that amount of time he kills off pretty much half the main cast, creates the base of the Super Polymerization card that fuels much of the remainder of the season's arc and sets up Jaden's dark turn that leads him to becoming the Supreme King.
• Yuri!!! on Ice:
  • The Nishigori triplets are relatively minor characters who tend to provide comic relief and exposition about how figure skating competitions work. However, they're also the ones responsible for kicking off the plot by recording Yuri's reenactment of famous figure skater Victor Nikiforov's program and uploading it online; the video soon goes viral, which catches Victor's attention and leads him to become Yuri's coach.
  • Celestino, Yuri's former coach, is also a minor character, but if he hadn't dragged Yuri to a banquet that Yuri really didn't want to go to, Yuri and Victor would never have met properly, and Victor wouldn't have already been interested in Yuri before seeing the viral video, which ends up being important to the plot since it's strongly implied that this was when Victor began to fall in love with Yuri, leading to them becoming an Official Couple.

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